package org.example.reggie.filter;

import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.example.reggie.common.BaseContext;
import org.example.reggie.common.R;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经登录
 */
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    //路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest)servletRequest;
        HttpServletResponse response = (HttpServletResponse)servletResponse;

        String requestURI = request.getRequestURI();

        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/student/login",
                "/student/register",
                "/student/add",
                "/student/list",
                "/backend/index"
        };

        boolean check = check(urls, requestURI);
        //如果不需要处理则直接放行
        if (check) {
            filterChain.doFilter(request,response);
            return;
        }
        //判断登录状态，如果已经登录，则直接放行
        if(request.getSession().getAttribute("employee") != null){
            Long empId = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(empId);

            filterChain.doFilter(request,response);
            return;
        }
        if(request.getSession().getAttribute("student") != null){
            Long stuId = (Long) request.getSession().getAttribute("student");
            BaseContext.setCurrentId(stuId);

            filterChain.doFilter(request,response);
            return;
        }
        if(request.getSession().getAttribute("sName") != null){
            Long studnetId = (Long) request.getSession().getAttribute("sName");
            BaseContext.setCurrentId(studnetId);

            filterChain.doFilter(request,response);
            return;
        }
        //如果未登录则返回未登录结果，通过输出流方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }
    public boolean check(String[] urls,String requestURI){
        for (String url : urls){
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }
}
